Role of endoneural cells in experimental allergic neuritis and characterisation of a resident phagocytic cell

Electrophysiological, clinical and histological techniques were used to monitor the time course of events related to experimental allergic neuritis (EAN) in 48 Lewis rats. The primary lesion was found to be paranodal demyelination without cellular infiltration. Endoneural phagocytes derive from hematogenous ED1+ED2- monocytes and possibly from resident ED1-ED2+ monocytic cells, not from Schwann cells and fibroblasts. We demonstrate a population of monocytic Ia-bearing, ED1-ED2+ spindle-shaped cells residing in normal peripheral nerve and provide evidence for their transformation into macrophages in the course of EAN.